System for the preparation of multiple solid state samples, in particular for spectroscopic and microscopic analysis

ABSTRACT

A system for the preparation and handling of multiple solid state samples, in particular for spectroscopic and microscopic analysis. The system comprises a sample holder assembly for multiple solid-state samples. The sample holder assembly comprises a sample holding body having first and second sides ( 3   a,    4   a ), provided with multiple sample receiving open-ended bores ( 5 ) extending through said body between said first and second sides, each bore ( 5 ) having a first opening at the first side and a second opening at the second side. Furthermore a closure body ( 10 ) is provided adapted to be mounted against the second side of the sample holding body, said closure body ( 10 ) having a closure side adapted to rest against the second side of the sample holding body for closing off the second openings of the bores ( 5 ) in said sample holding body. Compacting ( 23 ) means are provided for compacting samples filled in bores ( 5 ) of the sample holding body as these bores are closed off on the second side by the closure body.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the National Stage of International Application No.PCT/NL02/00472, filed Jul. 15, 2002, the contents of which isincorporated by reference herein.

FIELD OF THE INVENTION

The present invention relates to a system for the preparation andhandling of multiple solid state samples, in particular forspectroscopic and microscopic analysis.

BACKGROUND

In U.S. Pat. No. 5,675,410 a sample holder for a single sample isdisclosed. This sample holder has an open ended bore with a first andsecond opening, the bore being delimited by an annular wall.

In order to prepare a sample the sample holder is placed on a closurebody, thereby closing of the second opening of the bore.

The material to be sampled is introduced in the bore and then compactedusing a compacting means. Once the sample is prepared the sample holderis placed in an analyser, in particular a spectroscopic analyser.

The known system is ineffective in case a large number of samples are tobe analysed.

OBJECT OF THE INVENTION

The object of the present invention is to provide an improved samplepreparation system for the preparation of a multitude of solid samples,in particular for spectroscopic or microscopic analysis.

SUMMARY OF THE INVENTION

The present invention achieves this object by a system for thepreparation and handling of multiple solid-state samples, in particularfor spectroscopic and microscopic analysis. This system comprises asample holder assembly for multiple solid-state samples.

The sample holder assembly comprises a sample holding body having firstand second sides, provided with multiple sample receiving open-endedbores extending through said body between said first and second sides,each bore having a first opening at the first side and a second openingat the second side.

A closure body is provided and is adapted to be mounted against thesecond side of the sample holding body, said closure body having aclosure side adapted to rest against the second side of the sampleholding body for closing off the second openings of the bores in saidsample holding body.

The system further comprises compacting means for compacting samplesfilled in bores of the sample holding body as these bores are closed offon the second side by the closure body.

This new system is advantageous at the stage of preparation of thesamples, as many samples can be prepared quickly. Another advantage isthat all the samples are held in a common sample holding body, so thatthe samples can be analysed quickly without the need to remove a sampleholder and replace it for another. Also the focussing or similaradaptation of the spectroscopic or microscopic analyser on a new sampletakes less time than if separate sample holders are used, in particularif the surface of the samples all lie accurately in a single plane.

Another advantage of this system is the fact that it allows thepreparation of a multitude of sample surfaces for analysis, and alsoenables preservation of that surface during storage and transport.

The invention further relates to a sample holding assembly.

Preferred embodiments of the system and sample holder assembly accordingto the invention are described in the claims and the followingdescription referring to the drawings.

The present invention also relates to a method for the preparation ofmultiple samples and the spectroscopic and microscopic analysis ofmultiple samples using the system described herein.

The present invention also relates to the use of a sample holderassembly as described in a spectroscopic or microscopic analyser.

The system according to the invention is suitable in particular forspectroscopic and microscopic techniques such as reflectivecharacterisation methods:

-   -   XPS or X-ray photoelectron spectroscopy,    -   XRD or X-ray diffraction,    -   Auger electron spectroscopy,    -   SIMS or secondary ion mass spectroscopy,    -   DRIFT or Diffusive reflection infrared Fourrier-transform        spectroscopy,    -   SEM or Scanning electron microscopy,    -   EELS or Electron energy loss spectroscopy,    -   Raman scattering,    -   RAIRS or reflection absorption infrared spectroscopy,    -   IRES or infrared emission spectroscopy,    -   RBS or Rutherford Backscattering spectroscopy,    -   LEIS or low energy ion scattering,    -   STM Scanning tunneling microscopy,    -   AFM Atomic force microscopy,        as well as transmissive characterisation methods:    -   Mössbauer spectroscopy,    -   EXAFS or X-ray absorption fine structure spectroscopy,    -   Transmission infrared spectroscopy.        It will be apparent that the methods referred to above are        merely examples of suitable techniques.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 shows an example of a system according to the invention incross-section,

FIG. 2 shows the parts of the system of FIG. 1 in disassembled state,

FIG. 3 shows a plan view of the sample holder body of FIGS. 1 and 2, and

FIG. 4 shows a cross-section of an alternative sample holder assemblyaccording to the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

An example of a system for preparing and handling multiple solid statesamples, in particular for spectroscopic analysis, according to theinvention will now be described referring to the FIGS. 1-3.

The system comprises a multiple sample holder assembly 1 for solid-statesamples. This sample holder assembly 1 is assembled from a number ofparts including a sample holding body 2 having a first side 3 and asecond side 4, provided with an array of multiple sample receivingopen-ended bores 5 extending through said body 2 between said first side3 and second side 4.

Each bore 5 has a first opening 3 a at the first side 3 and a secondopening 4 a at the second side 4.

The bores 5 are arranged here in a pattern of parallel rows and columns,however other patterns are also possible.

In a practical embodiment the sample holder body 2 is formed from asolid block, e.g. a metal block, wherein the bores 5 have been machinedusing suitable tooling.

The assembly 1 further comprises a closure body 10 adapted to be mountedagainst the second side 4 of the sample holding body 2.

The closure body 10 has a closure side 11 adapted to rest against thesecond side 4 of the sample holding body 2 for closing off the secondopenings 4 a of the bores 5 in said sample holding body 2.

The system further comprises compaction and support plugs 15, which areeach adapted to be fitted in a bore 5 via the first opening 3 a. In theembodiment shown here a plug 15 slides smoothly inside the correspondingbore 5. In this embodiment the plugs 15 are preferably made from a hardmaterial, preferably having a minimum tensile strength of 10 MPa, morepreferably 50 MPa, most preferably 100 MPa.

The system shown in FIGS. 1-3 further comprises a compacting device 20adapted for pushing each of the plugs 15 into the bore 5 therebycompacting the sample. The compacting device 20 comprise a support 21removably fixed over the first side of the sample holding body 2 withthe interposition of a spacer 22.

The support 21 has screw threaded holes aligned with the bores 5 andprovided with screws 23 for pushing the plugs 15 into the bores 5,thereby compacting the samples.

The second side 4 a of the sample holder body 2 has a planar surface andthe corresponding face of the closure body 10 also has a planar surface11. Preferably the planar surface 11 of the closure body 10 is amirror-finished or mirror quality surface, so as to obtain a very highquality surface of the samples at the second side 4 a of the sampleholder body 2.

For instance the planar surface 11 of the closure body 10 is polished.

Preferably the planar surface 11 of the closure body 10 is hard to avoidany deformation of the surface and to avoid any contamination of thematerial of the closure body onto the sample surfaces. Preferably thehardness of this planar surface is greater than 6 Mohs, more preferablygreater than 7 Mohs and most preferably greater than 8 Mohs in order toprevent scratching of the planar surface 11.

It is envisaged that the planar surface 11 of the closure body 10 is oneof the following materials: glass, ceramic, aluminumoxide, silicon,siliconcarbide, titaniumnitride, although other materials having asuitable hardness are also possible.

In the embodiment shown in FIGS. 1-3 an additional support body 30 isfitted to cover the outside of the closure body 10, which preventsoverloading and/or distortion of the closure body 10, e.g. as theclosure body is made of glass.

In order to prepare the samples using a system according to theembodiment shown in FIGS. 1-3 the support body 30, closure body 10 andsample holder body 2 are assembled, e.g. using bolts connecting thesample holder body 2 to the support body 30 clamping the closure body 10there between.

Then the samples are introduced into bores 5 through the first openings3 a of the sample holder body 2.

The samples may for instance be introduced in the form of a powder (fineor coarse). The samples may also be introduced in the form of a slurryor paste, which then may be dried wholly or partly after introduced intothe sample receiving bores 5.

In a possible embodiment the powder is grinded before introduction intothe sample receiving bores, e.g. to a grain size of less than 0.5millimetres.

Then the plugs 15 are introduced into the bores 5 in order to compactthe samples between the stern face of the plugs 15 and the closure body10. Preferably provision is made for air escape passages in order toallow the escape of air from the space beneath a plug 15. In practicethis can be done for example by a suitable small play between the plug15 and the wall of the bore 5, for example by selecting a slightlysmaller space diameter plug than that of the bore 5.

After insertion of the plugs 15 the support 20 is fitted and the screws23 are thigtened to push the plugs 15 into the bores 5.

In practice compacting could be done with pressures above 1 kg/cm2,preferably above 10 kg/cm2.

The compacting device can be adapted for sequentially compacting thesamples of the simultaneous compacting of more than one or all of thesamples.

After suitable compaction of the samples the sample holder assembly inits closed state can be transferred to a spectroscopic or microscopicanalyser and mounted therein, for instance on a sample handling device

Then the support plate 30 and the closure body 10 are removed in orderto expose the faces of the samples at the side of the planar surface 4a. The samples can then be subjected to e.g. a reflective spectroscopicanalysis, whereby the samples are still supported by the plugs 15.

A major advantage is that the exposed surfaces of the samples all lieaccurately in a single plane 4 a, which allows the spectroscopic ormicroscopic analyser to analyse each sample without the need to(totally) refocusing every time a new sample has to be analysed. Thisgreatly reduces the time required for analysis of multiple samples incomparison to know single sample holders.

The sample holder assembly also allows for the parallel analysis of allor multiple samples in the sample holder.

Also the sample holder assembly does allow the samples to be treatedphysically or chemically prior to the spectroscopic or microscopicanalysis. For instance, the samples can be heat treated in a reducing oroxidizing atmosphere to get them in the desired chemical or physicalstate. If the spectroscopic or microscopic technique and equipmentallows this, these pretreatments can also be performed “in-situ”. Inthis case the samples can be analysed during the pretreatment, or evenunder actual reaction conditions. Especially in the field of catalysisresearch and development this is highly desirable.

To enable treatment at elevated temperatures under various gasatmospheres extra means can be added to the sample holder assembly.Heating means may be connected externally or even integrated in thesample holder body. Means for the supply of gas can be attached as well.Also closure means may be used to guarantee exclusion of air and/ormoisture from the environment after treatment during transport and/orstorage of the samples. Those skilled in the art will understand thevarious measures to accommodate these extra means.

In FIG. 4 a variant of the sample holding assembly of FIGS. 1-3 isshown. Parts corresponding to parts in FIG. 1-3 have the same referencenumeral.

In this embodiment the plugs 40 are expandable in diameter under axialcompression, either locally or over their entire length. Thereby theplugs 40 can be fixed in the bores 5 by expansion of the diameter. Theseplugs 40 are preferably made from a ductile material, preferably ametal, preferably having a maximum tensile strength of 400 Mpa, morepreferably 350 Mpa, most preferably 300 Mpa.

It is conceivable that the samples in the bores 5 are compacted firstusing a compacting device in combination with compaction plugs. To do sothe samples are filled in the bores 5 and then the compaction plugs areplaced in the bores 5. By pressing these compaction plugs into the bores5 further the samples are compacted. For instance the compaction deviceis a press (hydraulic, mechanical or simply a weight), a hammer (such ase.g. a pneumatic hammer). The compaction plugs can be integral with thecompaction device or separate parts. After compaction these compactionplugs can be removed and then the support plugs 40 are put into place.

It is also conceivable that the compaction plugs remain in the bores 5and that support plugs are placed in the bores behind the compactionplugs.

As an alternative means for securing plugs in the bores 5 an adhesivecan be used.

In another variant the bores 5 are provided with screw thread (at leastover a part thereof) and the plugs are also provided with screw thread,so that the plugs can be screwed into the bores 5 directly in order tocompact the samples and also to hold the plugs in place. It will beclear that these screw plugs can also be used if compaction is doneusing other means and the plugs only serve to support the compactedsamples.

It will be apparent that the compacting means for compacting samplesfilled in bores of the sample holding body can also be designed as meanswhich are not to be fitted on the sample holder, e.g. as a (hydraulic)press for pushing each plug into the bore. Also other locking meanscould be provided to lock each plug in place after compaction of thesample.

It is also envisaged that the plugs are removed from the sample holderbody before analysis of the samples. This is for instance relevant ifthe samples are to be subjected to a transmissive spectroscopicanalysis. In particular when using this technique it can be advantageousthat the thickness of the sample is measured, e.g. by measuring theposition of the plug in the bore.

The bores 5 are shown to have a circular cross-section, however othercross-sections are possible as well.

Preferably the bores 5 have a diameter less than 2 cm, more preferablyless than 1 cm, most preferably less than 0.5 cm, e.g. between 2 and 4millimetres.

The system allows handling and transportation of the sample holder usinga robot, which allows efficient loading of the samples into the samplereceiving bores 5.

Also the sample holder does allow the samples to be subjected to otheranalysing techniques than spectroscopy, or even allows the samples firstto be subjected to spectroscopy and then to another technique.

1. A system for the preparation and handling of multiple solid statesamples for spectroscopic and microscopic analysis, said systemcomprising: a sample holder assembly for multiple solid-state samples,said sample holder assembly comprising: a sample holding body havingfirst and second sides, provided with multiple sample receivingopen-ended bores extending through said body between said first andsecond sides, each bore having a first opening at the first side and asecond opening at the second side, a closure body adapted to be mountedagainst the second side of the sample holding body, said closure bodyhaving a closure side adapted to rest against the second side of thesample holding body for closing off the second openings of the bores insaid sample holding body, compacting means for compacting samples filledin bores of the sample holding body as these bores are closed off on thesecond side by the closure body, and plugs, each of the plugs adapted tobe introduced into one of the bores via the first opening, wherein theplugs are support plugs associated with said sample holding assembly,each support plug being adapted to be secured with respect to said borefor supporting a sample in said bore during at least one of thespectroscopic and microscopic analysis such that all exposed surfaces ofthe samples lie in a single plane.
 2. System according to claim 1,wherein the plugs are also compaction plugs associated with saidcompaction means for compacting a sample in said bore.
 3. Systemaccording to claim 1, wherein the plugs are compacting and support plugsfor compacting a sample in said bore and also adapted to be secured withrespect to said bore for supporting the compacted sample in said bore.4. System according to claim 1, wherein the plugs are slideable in thebores and the compacting means are adapted for pushing the plugs intothe bores thereby compacting the samples.
 5. System according to claim1, wherein the plugs are diametrically expandable under axialcompression such that the plugs allow for expansion and thereby fixationin said bores.
 6. System according to claim 1, wherein the plugs and thebores are screwthreaded.
 7. System according to claim 1, wherein thesystem further comprises securing means for securing the plugs in thebores.
 8. System according to claim 7, wherein the securing meanscomprise an adhesive.
 9. System according claim 1, wherein the systemwherein the compacting means comprise a support removably fixed over thefirst side of the sample holding body, said support having screwthreadedholes aligned with the bores and provided with screws for pushing theplugs into the bores.
 10. System according to claim 9, wherein theplanar surface of the closure body is a mirror-quality surface. 11.System according to claim 9, wherein the planar surface of the closurebody is polished.
 12. System according to claim 9, wherein the planarsurface of the closure body is one of the following materials: glass,ceramic, aluminumoxide, silicon, siliconcarbide, titaniumnitride. 13.System according to claim 1, wherein the second side of the sampleholder has a planar surface and wherein the corresponding face of theclosure body also has a planar surface.
 14. System according to claim 1,wherein the bores have a diameter less than 2 cm.
 15. System accordingto claim 1, wherein the hardness of the closure side of the closure bodyis greater than 6 Mohs.
 16. A method for preparing multiple samples forspectroscopic and microscopic analysis, comprising: providing of asystem for the preparation and handling of multiple solid state samplesfor spectroscopic and microscopic analysis, said system comprising asample holder assembly for multiple solid-state samples, said sampleholder assembly comprising: a sample holding body having first andsecond sides, provided with multiple sample receiving open-ended boresextending through said body between said first and second sides, eachbore having a first opening at the first side and a second opening atthe second side, a closure body adapted to be mounted against the secondside of the sample holding body, said closure body having a closure sideadapted to rest against the second side of the sample holding body forclosing off the second openings of the bores in said sample holdingbody, compacting means for compacting samples filled in bores of thesample holding body as these bores are closed off on the second side bythe closure body, plugs, each of the plugs adapted to be introduced intoone of the bores via the first opening, filing each sample into one ofthe a bores via the first opening thereof, said bores being closed atthe second side by the closure body, and compacting the samples usingsaid compacting means, wherein the samples are supported by said supportplugs such that during at least one of the spectroscopic and microscopicanalysis all exposed surfaces of the samples lie in a single plane. 17.A method according to claim 16, wherein a thickness of the compactedsamples is at least 100 micrometer.
 18. A method according to claim 16,wherein a thickness of the sample is measured.
 19. A method according toclaim 16, wherein the closure body is removed from the second side ofthe sample holding body thereby exposing the corresponding surface ofthe samples, and then subjecting the samples to spectroseopic ormicroscopic analysis.
 20. A method according to claim 19, wherein thesamples are subjected to a physical or chemical treatment prior to orduring the samples to spectroscopic or microscopic analysis.
 21. Amethod according to claim 19, wherein the bores are open between thefirst opening and the sample so that also the surface of the samplesdirected towards the first side of the sample holder body are exposed,and subjecting the samples to a transmissive spectroscopic analysis. 22.A system for the preparation and handling of multiple solid statesamples for spectroscopic and microscopic analysis, said systemcomprising: a sample holder assembly for multiple solid-state samples,said sample holder assembly comprising: a sample holding body havingfirst and second sides, provided with multiple sample receivingopen-ended bores extending through said body between said first andsecond sides, each bore having a first opening at the first side and asecond opening at the second side, a closure body adapted to be mountedagainst the second side of the sample holding body, said closure bodyhaving a closure side adapted to rest against the second side of thesample holding body for closing off the second openings of the bores insaid sample holding body, and compacting means for compacting samplesfilled in bores of the sample holding body as these bores are closed offon the second side by the closure body, and plugs, each of the adaptedto be introduced into one of the bores via the first openings, whereinthe plugs are support plugs associated with said sample holdingassembly, each support plug being adapted to be secured with respect tosaid bore for supporting a sample in said bore during at least one ofthe spectroscopic and the microscopic analysis such that all exposedsurfaces of the samples lie in a single plane, and wherein thecompacting means comprise a support removably fixed over the first sideof the sample holding body, said support having screwthreaded holesfixed over the first side of the sample holding body and aligned withthe bores and provided with screws for pushing the plugs into the bores,and wherein the second side of the sample holder has a planar surfaceand wherein the corresponding face of the closure body also has a planarsurface, which planar surface is polished, is a mirror-quality surface,and is one of the following materials: glass, ceramic, aluminiumoxide,silicon, siliconcarbide, titaniumnitride.